Association of symptoms of depression with progression of CKD

Background: Depression is related to morbidity and mortality in patients with kidney failure treated by dialysis, but its influence on patients with earlier stages of chronic kidney disease (CKD) is uncertain. This study investigates the association of depressive symptoms with clinical outcomes in patients with CKD not requiring dialysis.

Study design: Prospective observational cohort study.

Setting & participants: 568 participants with CKD not requiring maintenance dialysis were recruited consecutively at a tertiary hospital in Southern Taiwan and followed up for 4 years.

Predictors: Baseline status of depressive symptoms.

Outcomes: The primary outcome is a composite of progression to end-stage renal disease (ESRD), defined as requiring maintenance dialysis treatment, or all-cause mortality; and secondary outcome was first hospitalization.

Measurements: Depressive symptoms were assessed by Beck Depression Inventory. Estimated glomerular filtration rate (eGFR) was computed using the 4-variable MDRD (Modification of Diet in Renal Disease) Study equation.

Results: 428 participants completed the questionnaires and 160 (37%) had depressive symptoms. During a mean follow-up of 25.2 ± 11.9 months, 136 participants (32%) reached the primary outcome (119 reached ESRD and 17 died) and 110 participants (26%) were hospitalized. High depressive symptoms increased the risk of progression to ESRD or death (HR, 1.66; 95% CI, 1.14-2.44) and first hospitalization (HR, 1.59; 95% CI, 1.03-2.47). Participants with high depressive symptoms had more rapid GFR decrease (eGFR slopes of -2.3 [25th-75th percentile, -5.3 to -0.4] vs -1.2 [25th-75th percentile, -3.5 to 0.3] mL/min/1.73 m(2) per year; P = 0.001) and initial dialysis treatment at a higher eGFR (OR for initiation of dialysis at eGFR >5 mL/min/1.73 m(2), 4.45; 95% CI, 1.44-13.78).

Limitations: A single-center study of Taiwanese, Beck Depression Inventory evaluates only depressive symptom burden.

Conclusions: Depressive symptoms in CKD are independent predictors of adverse clinical outcomes, including faster eGFR decrease, dialysis therapy initiation, death, or hospitalization. Depression should be evaluated early and treated in patients with CKD.